Method of and apparatus for making molds



May 30, 1933. w s 1,911,542

METHOD OF AND APPARATUS FOR MAKING HOLDS Filed Oct. 24. 1931 4 Sheets-Sheet l HENRY A WI/RSTEP May 30,1933. H. A. WURSTER METHOD OF AND APPARATUS FOR MAKING HOLDS Filed Oct. 24. 1931 4 Sheets-Sheet 2 w Wm,

gr voantoa y 0, 1933. H. A. wuRsTER 1,911,542

METHOD OF AND APPARATUS FOR MAKING MOLDS Filed Oct. 24, 1931 4 Sheets-Sheet 3 I a g a ,1 & a: I;

gmnntoz May 30, 1933. H. A. WURSTER METHOD OF AND APPARATUS FOR MAKING MOLDS Jwuemtov @MQ Zi 4 Sheets-Sheet 4 Filed Oct. 24, 1931 HENRY A. WU/PSTf/ Patented May 30, 1933 UNITED STATES PATENT OFFICE HENRY A. WUBBTER, F CLEVELAND, OHIO Application filed October 24, 1931. Serial No. 570,829.

This invention relates to a method of and apparatus for making molds for use in the manufacture of castings, and while not limited thereto, the invention has particular utility in foundries where different types of parts castings are desired to be produced on a yolume basis, and also in foundries which produce an entire assembly of castings going to make up a complete machine or article regardless of whether or not volume production is contemplated, the present invention in any event providing a method which considerably reduces the costs of production, as will hereinafter appear. In foundries of the foregoing type, it has heretofore been customary to assign a workman to each particular line of castings. Since this workman has to carry on all of the mold-making operation, he comes under the class of skilled in labor and rates pay accordingly. F urthermore, considerable time is consumed when one or more men work on one line of castings, as for example in moving about from one point or from one machine to another.

The cost of production in suchractice is much higher than where unskilled workmen are assigned to a certain part of the moldmaking operations, as in volume production of a single line of castings. Obviously it is not practicable to adopt this latter practice where the demand for certain arts is limited to, say, one or two parts or an entire machine or article.

It is an important object of the present invention, therefore, to provide a method and apparatus, or coordinated arrangement of parts, for will produce a line of different t s of castings for the same, or substan'tia y the same,

cost as where a single line of castings is produced on a volume basis. More specifically, the invention contemplates a method and ap aratus for maki -molds for a variety o castings in a continuous c jcle without the aid of skilled labor and without detracting from the quality of the mold to be 7 produced.

Another object of the invention is to provide a method and apparatus whereby the costs of making each mold for various parts making molds for castings which castings will be substantially the same regardless of the size and/or shape of the casttaken in conjunction with the drawings,

wherein:

Figure 1 is a view in plan and generally diagrammatic of a type of apparatus suit- 0 able for carrying out my method;

Figure 2 is a view in side elevation thereof;

Figures 3, 4 and 5 are views in transverse vertical section taken respectively on the lines III-III, IV-I and v1 vI, Fig. 1; and

Figure 6 is an enlar ed view of Figure 5 to more clearly show t e parts of the unit.

Generally stated, the method consists in advancing a series of interchangeable cope and drag lates in a continuous cycle together with mol flasks or the like into a position to receive molding sand, or like material, and also adjacent various fabricating units, the sand being poured and then packed, after which the flasks and molds are removed from the plates and the parts of the mold matched and placed in position ready for the pouring opslration, the plates and flasks repeating the Cy e. 39 Referring to the drawin s, in Figure 1 the main conveyor is genera y indicated at 5. The conveyor may be of any suitable type and in the instance shown comprises a track 6 which may be supported directl on the as ground or on a suitable concrete but,

or the purpose of illustration, is shown in the present instance as supported on a pedestal 7, note Figures 3, 4 and 5. If the tracks .are to be supported directly on the ground 00 orfloor, it is only necessary to provide a suitable pit for a purpose which will later be described. The tracks 6 are arranged in a continuous cycle as shown in Figure 1. The mold parts are carried on a series of conveymg and stripping machines, nerally indicated at 8 One of these mac 'nes is shown enlarged in Figure 6, each machine bein formed with a base 8a, which is mean on a conveyor element or truck 90 provided with track wheels 9, and a flat top portion or table 10. Mounted to reci rocate vertically in the central portion 0 the machine is a jarring plunger 11, which is provided with a roller 12 in the lower end thereof, the plunger being retained in limited reciprocating position by means of an annular collar 13. This plunger operates in a manner and for a purpose which will presently be described. Each machine is also provided with a flask and mold removingl or stripping assembly comprising a cross ead or analogous member 14, which is mounted for limited vertical movement in the machine frame and is provided with track wheels or rollers 15 and pins or vertically extending rods 16 which are shown threaded into the cross head 14 and locked in position by means of nuts 17. Each machine is also provided with a vibrator,'

generally indicated at18. This vibrating device may be of any suitable type, it being preferred in the present instance to provide a vibrator which will shake the entire machine, although it will be obvious that other types of vibrators well known on the market may be used. The vibrator is cut on and off automatically by means of a limit switch 18a and contact member 186.

The machine just described, it will be noted, is so constructed that it will not only carr the mold parts but will provide a jarring member adapted to co-operate with a jarring machine, as well as the means above noted for removing the molds and flasks from the patterns at a proper time during the mold making cycle.

While the apparatus here shown is not fully automatic, it is so constructed and arranged that skilled labor may be entirely dispensed with. At various positions adjacent the path of, travel of the conveyor unit, unskilled attendants may be stationed. The machines are rovided with plates 19, note for example igure 6. These plates are paired, oneof the plates carryingthe cope portion of the usual match plate pattern while the adjacent plate carries the drag pattern, as indicated in dotted lines at 20, and ma therefore be termed the cope and drag p ates. The plates 19 are secured to the truck tops or tables 10 in any well known manner and are formed with holes or bores 21 for a purpose to be described. These plates 19 are interchangeable with respect to each machine 8. Assuming the plates 19 with the pattern parts secured thereon to be already mounted on the machines 8, an unskilled attendant (or automatic means not shown) is-positioned at A, Figure 1, and cleans and dusts the plates as the pass around on the conveyor 5, the latter being driven in any suitable manner not shown. At B, the flasks, indicated at 22, are removably' applied to the plates, each flask being provided with upper and lower flanges 23 and 23a.

The mold parts are now ready to receive the molding sand. The molding sand is taken from a suitable pit-or source of supply and'carried up by an elevator generally indicated at 23 which may be of any approved type. The sand from the elevator falls by gravit into a hopper 24, note Figure 2, from which it falls onto a conveyor 25. Adjacent the conveyor is a combined scraper and chute 26 which scrapes a certain portion of the sand off the conveyor and guides it into the flasks as they pass thereeneath. To insure an ample supply for each mold, a certain portion of the sand is permitted to pass to the end of the conveyor and augment that already in the molds. It will thus be seen that the supply of sand may be regulated so that the molds will be substantially filled by the device 26, and then completely filledor stacked by the remaining sand passing over they end of the conveyor. Due to the fact that ample provision is made to take care of the surplus sand, the supply of sand may be adjusted to take care of each and ever mold'regardless of its size.

Tile method of conserving and utilizing the surplus sand is clearly illustrated in F i ures 2, 3, and 4. A it 27 is rovided beneat the conveyor 5 an over t is pit a grating 28 is mounted. On each side of the grating and extending downwardly from the latter inclined walls are provided defining a hopper 29, the sand falling through the grating being guided by said hopper onto a return conveyor 30. As shown, this conveyor is mounted on rollers 31, which are journalled in bearing pedestals 32 in the pit 28. The pit 28 extends a substantial distance outwardly beneath the mold conveyor 5 so that all of the surplus sand that may be removed from, or fal off, the molds is received by the conveyor 30 and taken back and dumped onto a chute 33 from which it axes by gravity into the bottom of the pit neath the elevator 23.

The mold parts and flasks 22, u onbein supplied with loose molding san are mf vanced on the machines 8 over an automatic jarring unit 34, note Figures 2 and 3. This Larring unit or machine ma be of an well nown type and is provided with a p unger 34a and top 346 adapted to contact with the roller 12 as' the latter passes thereover and imparts a series of blows to the plunger 11, which in turn strikes the bottoms of the plates 19 and jars the'molds. In the event it IS desired to lengthen the duration of the jarring period, the head 34b ma be elongated in the direction of trave or other y means adopted. Ordinarily, however,aregulation' type of head 346 will be of ample size. The jarring machine is preferably cut on and oil automatically by means of a knee valve or cam 340, see Figure 3.

The machines 8 now advance beneath a scraper, note Figure 1, or leveler 35, which is mounted immediately above the path of travel of the molds and is preferably adjustable so that it may be inclined to varying positions. This device 35 levels the sand and scrapes the surlplus off onto the conveyor 30 in the pit 28. ue to the fact that the latter extends a substantial distance beyond the member 35, any loose sand which may fall from the molds after passing this point will also fall onto the conveyor 30 and be returned to the elevator 23.

At station 0, Figure 1, an unskilled attendant places tops or boards 36 on the cope and drag. The molds are now ready for the squeezin or final tamping action which is preferab y performed automaticall by a squeezer, generally indicated at 37 igure 4. This device may be of any suitable type and is provided with a head 37a adapted to descend as the mold passes'therebeneath and contact with the boards 36 and pack the sand in the flasks 22. The squeezer 37 is also preferably automatically cut on and off by means of a knee valve or the like as at 37b.

From this position the molds advance to station D where the cope boards are removed and placed on a return conveyor 38, which conveys the boards back to the point where they were originally applied to the molds. At E, an attendant forms suitable sprue holes in the cone, although it will be understood that this operation may, in some instances, be performed automatically without departing from the scope of the invention.

The molds are now ready for removal of the flasks and molds from the cope and drag. This operation is performed automatically by the mechanism heretofore described in connection with the machines 8 co-operating with the track system particularly shown in Figure 2. A mold and flask-lifting track 39 is mounted on a plane above the main tracks 6 as shown in Figures 5 and 6, said track being provided with ramps 39a and 39b at each end thereof. When thetracks 8 reach the ramp 39a, the rollers or wheels 15 engage the tracks 39, elevating the cross head 14 and flask-lifting pins 16, the latter engaging the flange 21 of each flask 22 and stripping the flask and mold from the pattern.

To prevent sticking of the molds, the vibrator 18, heretofore referred to, is started in operation automatically, preferably between the station E and ramp 39a, by the limit switch 18a and contact member 186 mounted ad'acent the path of travel of the trucks 8. t will be understood that the vibrator could be started and/or sto ped manually by an attendant if desired. Ilowever, it is preferred to start and sto the vibrator automatically, as above speci ed.

When the flasks and molds have been stripped clear of the patterns, they are placed on a conveyor 40 by an attendant stationed at F, which conveyor returns them to a point adjacent the station B ready to repeat the cycle. The attendant then removes and pairs t e mold parts and then applies a suitable band or jacket, not shown, and the assembled mold is now ready for the pouring operation. If required, the attendant may insert a core or cores prior to pairing the molds. The assembled molds may be placed on a conveyor not shown and taken to any suitable point for pouring, or the molds may be disposed of .in any suitable manner, as desired.

It is of advantage to space the core molds alternately with respect to the plain molds, so that the attendant will have more time to insert the cores than where the core molds are arranged in series.

From the foregoing, the operation of the apparatus will be readil understood. Briefly, however, an example of one preferred method of operation is as follows:

The cope and drag plates 19, as will be understood, may be secured to the tops or tables 10 of the trucks 8 and repeat the cycle until it is desired to change the casting.

The machines 8 and plates 19, therefore, move in a continuous cycle, preferably without interruption. At station A an attendant cleans and dusts the patterns or plates 19 and at B the attendant places the flasks on said plates, which flasks may be taken from the conveyor 40. When the machines with the cope and drag plates and flasks thereon reach a point below the device 26, theyare filled or substantially filled, with molding sand, this operation being completed when the flasks pass beneath the end of the conveyor 25. When the machines 8 pass over the jarring unit 34, the molds are subjected to a jarring action, after which the scraper 25 scra es the excess sand from the tops of the flas s. At C an attendant applies suitable top boards over the cope and the drag constituting the mold sections, after which the squeezer 37 operates on the flasks and the sand is firmly packed thereby. At station D, the boards are removed from the cope and placed on the conveyor 38 and returned to station C. At E an attendant forms a suitable sprue hole in the cope, after which the vibrator is set in operation preparatory to stripping of the flasks and molds from the patterns. This stri ping operation ensues when the track w eels 15 engage the ramp 39a. When the said wheels 15 pass onto the tracks 39 the flasks and molds will have been completely stripped from the patterns and the flasks may then be removed from the molds and placed on the return conve or F and returned to station B. The atten ant, if necessary, inserts a core or cores, and then pairs the sections and applies a suitable band therearound. The assembled mold is now ready for pouring.

It will be seen that by employing my system, molds for various types of castings may be made at a uniform rate of speed and at a uniform cost without the aid of skilled labor. The time and labor saved will be obvious and the costs of production may be lowered to a point where it is possible to operate foundries at a profit which under the methods heretofore followed could not aflord to keep the foundry running or which operated at a loss or a very small margin of profit. One conveyor system as herein illustrated and described can be added to or detracted from to accommodate a complete assembly of castin s, all of which may be produced with unskilled labor. While in system as herein disclosed is not complete y automatic, yet it can be made automatic or substantially so if desired within the scope of the invention. Since the time spent on each casting must be substantially the same, and since the labor employed in my system all work together to produce the entire assembly of castin the cost of each casting will be substantia ly the samei whether large or small, complex or siipf aving thus described my invention, what I claim is:

1. A system of making molds of varying sizes and shapes, which consists in advancing a series of interchangeable cope and drag plates or patterns in a continuous cycle in a substantially horizontal plane, cleani said plates and a plying flasks thereto at t e beinning of t e cycle, conveying sand in uniorm quantities to the flasks and packing the sand while the molds are travelin in said cycle, returning the excess sand to t e source of supply, and removing the molds and flasks and matching the mold parts at the termination of the cycle.

2. A system of making molds of varying sizes and shapes, which consists in advancing a series of interchangeable cope and drag plates or patterns in a continuous cycle in a substantially horizontal plane, cleaning the plates and applying flasks thereto at the beinning of t e cycle, conveying sand to the flasks and packing the sand while the molds are travelin in said cycle, removing the molds and asks and matching the mold parts at the termination of the cycle, and finally returning the flasks to a point adjacent the beginning of the cycle.

3. A system of making molds in varying sizes and shapes, which consists in mounting a series of interchangeable cope and drag plates or patterns on a conveyor adapted to travel in a continuous cycle, cleanin said plates and applying flasks thereto at t e beginni of the cycle, automatically filling each 0 the flasks with a uniform quantity 0 sand and packing the latter while the molds are traveling in said cycle, returning the excess sand to the source of supply, jarring the flasks and molds and then raising the molds and flasks from the patterns, removing the flasks and matching the mold parts at the termination of the cycle, and finall returning the flasks to a point adjacent t e beginning of the cycle.

&. The method of making molds, which consists in mounting a series of cope and dra plates or patterns on a series of stripping an conveying machines adapted to travel in a continuous cycle, cleaning said plates and applyin flasks thereto at the beginning of the cyc e, automatically ap lying the same quantity of sand to each of the flasks, jarring said flasks to settle the sand, scraping the excess sand from the to of the flasks and returning the excess san to the point of supply, squeezing the sand, forming sprue holes in the mold, vibratin the machines to loosen the molds and raising the molds and flasks from the patterns, all of the foregoing operations being performed while the molds are travelin in said cycle, and finally matching the mol parts and returning the flasks to apoint adjacent the beginning of the cycle.

5. Apparatus for making molds comprising a conveyor adapted to travel in a continuous unbroken cycle, interchangeable co and drag plates or patterns mounted on said conveyor and adapted to travel therewith, flasks detachably disposed on said match lates, means for automaticall filling said asks with sand or like molding material, automatically acting jarring mechanism mounted below said conveyor and adapted to 0 rate on said plates, a scraper for removing excess sand mounted above said conveyor, automaticall acting s ueezing mechanism also mounte above sai conveyor and adapted to operate on the sand in the flasks, means for automatically raising the molds and flasks from the patterns, and means for returning the excess sand to the point of 6. pparatus for making molds of varying sizes and shapes comprising a conveyor adapted to travel in a continuous cycle in a substantially horizontal plane, cope and drag plates or patterns mounted on said conveyor and adapted to travel therewith, flasks removably disposed on said plates, a sand conveyor for automatically fil ing the flasks with .uniform quantities of sand, arring mechanism mounted below said conveyor, a scraper mounted above said conveyor for removing excess sand, a pit below said conveyor for receiving the excess sand. a conveyor in said pit for returning the sand to the point of supply, means for packing the sand, and means for removing the molds and flasks from the patterns at the termination of the cycle.

7. Apparatus for making molds, comprising a series of conveyin and stripping ma- ChlIleS adapted to travel in a continuous cycle in a substantially horizontal plane, patterns and flasks carried by said machines, means for filling the flasks with sand and operating on the latter while traveling in said cycle, and return conveyors mounted adjacent said main conveyor for returning certain parts of the mold assembl to a point adjacent the beginning the cyc e.

8. Apparatus for making molds, comprisin a series of conveying and stripping machines adapted to travel in a continuous cycle in a substantially horizontal plane, interchangeable cope and drag plates or patterns mounted on said machines and adapted to travel therewith, flasks removably mounted on said plates, means for filling said flasks with sand and operating on the latter while the molds are traveling in said cycle, means for removing the molds and flasks from the patterns at the termination of said cycle, and a conveyor for returning said flasks to a point adjacent the beginning of the cycle.

9. Apparatus for making mo ds, comprising a track-way extending in a continuous cycle in a substantially horizontal plane, a series of conveying and stripping machines mounted on said track, interchangeable cope and drag plates or patterns mounted on said machines, flasks removably mounted on said plates, means for filling said flasks with sand and packing the latter while the machines are traveling in said cycle, and afurther track-way positioned adjacent sald first named track and co-operating with means carried by said machines for raising the molds and flasks from the patterns at the termination of said cycle.

10. Apparatus for making molds comprising a track extending in a contlnuous unbroken cycle in a substantially hor zontal plane, a series of conveying and stripping machines mounted on said track, each of sald machines being rovided with a top for supporting the mold parts. interchangeable cope and drag plates or patterns secured on said tops, flasks removably mounted on said plates, means for filling said flasks with sand and packing the latter while the machines are traveling in said cycle, vertically reciprocating members on said machines adapted to engage said flasks, and means for actuating said members for raising said molds and flasks from the patterns.

11. Apparatus for making molds, comprising a series of conveying and stripping machines adapted to travel in an unbroken cycle, interchangeable cope and drag plates or patterns mounted on said machines and adapted to travel therewith, flasks removably mounted on said plates, means for filling said flasks with sand and packing the latter while the molds are traveling in said cycle, vertical reciprocable pins mounted in said machines and adapted to engage said flasks, a cross head connected to said pins, wheels or rollers mounted in said cross head, and a track mounted adjacent the path of travel of said machinesfor reciprocating said cross head and said pins and stripping the molds and flasks from the patterns.

12. In apparatus for making molds, a series of conveying and stripping machines adapted to travel in a continuous unbroken cycle, each of said machines being provided with a top adapted to support the mold parts, a plunger mounted in each of said machines and movable vertically with respect to the latter, and jarring mechanism mounted beneath the path of travel of said machines for actuating said plunger.

13. In apparatus for makin molds, a series of conveying and stripping machines adapted to travel in a continuous cycle, jarring mechanism mounted below the path of travel of said machines, and a vertically reciprocable plunger mounted in each of said machines and adapted to contact with said jarring mechanism.

14. In apparatus for makin molds, a series of conveying and stripping machines adapted to travel in a continuous cycle, cope and drag plates or patterns secured on the to s of said machines, each of said machines being provided with vertically reci rocable mold and flask-removing members a apted to rise throu h said plates, means for actuating said mem ers, a jarring machine mounted beneath the path of travel of said machines, and a vertically reciprocable plunger carried by each machine adapted to contact with said jarring machine and said plates for jarring the molds while the conveying and stripping machines are traveling in their cycle.

15. In apparatus for making molds, a series of conveying and stripping machines adapted to travel in a continuous cycle, interchangeable cope and drag plates or patterns mounted on said machines, flasks removably mounted on said plates means for filling said flasks with sand and packing the latter during the cycle, a vibrator on each of said machines, mold and flask removing mechanism also provided on each of said machines, means mounted adjacent the path of travel of said machines for controlling said vibrator, and a system of tracks for actuating said flaskremoving mechanism, the vibrator being operated prior to the removal of the flasks.

In testimony whereof I hereunto aflix my signature this 16th day of October, 1931.

HENRY A. WURSTER. 

